Tektronix TR 502 Instruction Manual page 11

e. Rotate the VAR dB control through its range and
note that the display level decreases in accordance with
the calibrated scale on the front panel . Return the control
to its 0 dB position and/or the spectrum analyzer Ref Var
control to Cal .
a . Set the spectrum analyzer Reference Level to
+10 dBm and the Display Mode to 2 dB/Div . Set the
TR 502 OUTPUT LEVEL and VAR dB controls for an
output of 0 dBm (fully clockwise) .
b. Decrease the spectrum analyzer Freq Span/Div
towards 200 Hz while adjusting the TRACKING ADJUST
control for minimum frequency offset . This corresponds
to maximum response on the display. .
REV . A, MAY,1978
NOTE
Operating Instructions-TR 502
b. Decrease the TR 502 OUTPUT LEVEL to -50 dBm
Measuring Frequency
in 10 dB increments and increase the spectrum analyzer
The TR 502 features a sweep-stop operational mode
sensitivity in 10 dB increments . Note that the display level
that stops the sweep at center screen, centers the dot,
remains constant .
instructs the frequency counter to take a frequency
measurement, then allows the sweep to continue . Gate
c. Return the TR 502 OUTPUT LEVEL to 0 dBm,
(count) time is determined by the phase lock mode of the
analyzer . When the analyzer is phase locked, the frequen-
change the spectrum analyzer Freq Span/Div to 1 MHz
cy count is accurate to the nearest 10 Hz and when the
and the Display Mode to 2 dB/Div . Adjust the spectrum
analyzer is not phase locked the accuracy of the count is to
analyzer Ref Var control or the TR 502 VAR dB control to
the nearest 100 kHz. This sweep-stop mode can be
set the display at some graticule division .
switched off by the DOT INTENSITY control . Logic data,
to stop the spectrum analyzer sweep and operate the
d . Decrease the TR 502 OUTPUT LEVEL in 1 dB steps
counter, is transmitted through the interconnecting cable
between the TRACK GEN LOGIC connectors and the data
and note that the display level decreases proportionately.
lines between the interface connectors of the TM 503
Return the OUTPUT LEVEL and VAR dB control to 0 dBm.
Option 7, or other compatible TM 500-Series mainframes .
In the non-sweep (Manual or External) the count is
continuous . If the TR 502 is used with a 7L12 Spectrum
Analyzer, or the frequency counter is not compatible with
the operational logic of the TR 502, the analyzer should be
operated in the non-sweep modes to measure frequency.
3. Tracking Adjust
Connect and operate the system as follows:
This control adjusts theTR 502outputfrequencytothe
input frequency of the spectrum analyzer .
1 . Connect the AUX RF OUT through a 50 S2 cable to
the frequency counter Input . If the system has the
Tracking Generator Logic feature, connect the logic
interface cable to the TRACK GEN LOGIC connectors .
Note : TM 500-Series mainframe must have the data lines
between the interface connectors (Option 7 for TM 503) .
2. Turn the power on and set the VAR dB control to
zero .
3. With the 7L13 in the sweep mode, turn the DOT
INTENSITY on and adjust the brightness level of the
frequency dot .
4. Counter should now indicate the frequency of the
dot .
NOTE
If the TR 502 is used with a 7L13 Spectrum Analyzer
the TRACKING ADJUST may run out of range at
The sweep stop trigger level of the TR 502should be
high resolution (3 kHz or less) settings because the
adjusted to match the 7L13 center screen level .
IF in some early production 7L13 units may deviate a
Accuracy of the dot is not affected however . If a hole
small amount from 105 MHz. If this occurs, notify or
exists between the sweep stop point and the dot, it
contact your local Tektronix Field Office or
can be removed by referring to the Calibration
representative to correct this situation .
section for adjustment procedure .
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